Asbestos began to be used widely in the United States in the 19th century with the advent of steam for boats, ships, trains, and in factories. In the early years of its use, asbestos was not widely known as causing disease, and it was very helpful in society. In about the 1920s-1930s, evidence began building that asbestos was a significant health problem. I’m often asked, “Well, what did the companies know? Weren’t they really in the dark?” As a young lawyer when I pioneered this work in Michigan, the most significant piece of evidence that I found was that many companies that made asbestos, mined, sold, or milled asbestos had a great amount of knowledge about the health hazards of asbestos and never shared it with their workers or with consumers. And that is the gravamen of the liability case against these companies.